Bump version from 5.1.1 to 5.2.0

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: claude

Project.toml

@@ -1,7 +1,7 @@
 name = "DiffEqProblemLibrary"
 uuid = "a077e3f3-b75c-5d7f-a0c6-6bc4c8ec64a9"
 authors = ["Chris Rackauckas <accounts@chrisrackauckas.com>"]
-version = "5.1.1"
+version = "5.2.0"
 
 [deps]
 BVProblemLibrary = "ded0fc24-dfea-4565-b1d9-79c027d14d84"